U.S. Pat. No. 3,722,019 which issued to Walter Magnien in 1973 discloses a paint trimming apparatus which includes a detachable pad carried on a hand held housing. The housing has an angulated guide. A stop is provided against which engages the bristles of the pad holding them clear of the guide to prevent paint from being picked up by the guide during use.
Although useful, the paint trimming apparatus, as described, was subject to fouling. Furthermore, when it became fouled it was difficult to clean. As the guide became worn it became increasingly inaccurate until eventually the paint trimming apparatus lacked utility and had to be disposed of.